Synthesis of Novel Tetra- and Pentacyclic Benzimidazole Derivatives
作者:Kyongtae Kim、Jae Sang Yi
DOI:10.3987/com-02-9604
日期:——
3]thiazepino[3,2-a]benzimidazole 6,6-dioxide (1) with NaH (1.2 equiv.) for 30 min in THF at room temperature under nitrogen atmosphere, followed by addition of alkyl propiolate (4 equiv.) gave tetracyclic benzimidazole derivatives (7). Subsequent reactions of 7 with Na in p-xylene at reflux, followed by addition of HOAc at room temperature gave pentacyclic benzimidazole derivative (8) in good to excellent
7,12-二氢[5,6][1,3]噻氮杂[3,2-a]苯并咪唑6,6-二氧化物(1)用NaH(1.2当量)在THF中在室温下处理30分钟氮气氛,然后加入丙炔酸烷基酯(4当量)得到四环苯并咪唑衍生物(7)。随后,7 与 Na 在对二甲苯中回流反应,然后在室温下加入 HOAc,得到五环苯并咪唑衍生物 (8),收率良好。
A new solvent system for efficient synthesis of 1,2,3-triazoles
作者:Bo-Young Lee、So Ra Park、Heung Bae Jeon、Kwan Soo Kim
DOI:10.1016/j.tetlet.2006.05.079
日期:2006.7
The use of CH2Cl2 as a co-solvent with H2O in the copper(I)-catalyzed 1,3-dipolar cycloaddition of organic azides and alkynes increased reaction rates and provided the corresponding 1,2,3-triazoles in excellent yields compared to other organic co-solvent systems. Moreover, we applied this discovery to prepare the functional multivalent compound in an excellent yield.
A new alkyne protectinggroup, trispyrazolylborateplatinum(methyl) (TPM), that can tolerate various reaction conditions and is particularly useful for electron-deficient acetylenes allows for synthetic manipulations of polyfunctional acetylenes. This protectinggroup withstands a variety of reaction conditions, including basic and acidic media, and the environment required for catalytic hydrogenation
benzyl bromide 2 and cinnamyl bromide 3 give products which are dependent both upon the nature of the amine component of the enamine and, in the case of the amides, upon the amine from which the amide is derived. The β-enamino esters react with benzyl bromide to yield predominantly dialkylated products in the case of the pyrrolidine ester 1a. Reactions of the same esters with cinnamyl bromide yield
Lewis Base-Catalyzed One-Pot Cascade Sequences of <i>O</i>-Alkenyl-Substituted Cyanohydrins: Diastereoselective Synthesis of Multisubstituted Dihydrofurans
作者:Shan-Tao Du、Zhen Sun、Wei Liu、Wei-Wei Liao
DOI:10.1021/acs.orglett.7b03301
日期:2017.12.15
of the diastereoselective construction of polysubstituted 2,3-dihydrofurans incorporating contiguousquaternary and tertiarycarbon centers via a Lewis base-catalyzed one-pot cascade sequence is described. The diversity and complexity of the final products can be efficiently constructed with high diastereoselectivities via this catalytic multistep process under mild reaction conditions.